The present invention relates generally to traversing opening covering devices and more particularly to a traversable support for one or more horizontally-extending members or elements in such devices.
Traversing window or opening covering devices as used herein include vertical blinds, traversable draperies and similar traversable window and wall covering devices and traversable space separating devices. Common to such devices is one or more horizontally-extending members or elements. In vertical blind structures, the horizontally-extending member or element may be one or more rods used to effect traversing and/or rotation, or a cord or similar element used to effect traversing. For a traversable drapery, the horizontally-extending member may be the support rod and/or a cord or similar element used to effect traversing. The traversable support according to the invention prevents sagging of such horizontally-extending members or elements. The invention and its background will be further described in connection with vertical blinds, it being understood, however, that the invention and its use are not limited to vertical blinds.
Vanes of vertical blinds are usually supported by and suspended from members commonly referred to as carriers which themselves are traversably supported by a track structure. The carriers include means interconnecting them to limit the distance by which they may be separated; such means commonly comprise spacers or spacer links. The carriers also include means for mounting drive means for rotating the vanes and at least one of the carriers in the blind includes means by which the carrier may be moved along the track or traversed.
In one type of vertical blind structure, gearing is disposed in the carrier which, upon being driven, causes the vane suspended from the carrier to rotate. The gearing is driven by a horizontally-extending rotation rod. This type of blind structure is described in my U.S. Pat. No. 4,140,169 issued on Feb. 20, 1979, which is incorporated herein by reference. In this type of blind structure, the rotation rod is rotatably supported at its ends in the track structure with the rotation rod extending through the carriers. Since the rotation rod extends through the carriers, the carriers also support the rotation rod when the carriers and vanes are extended or traversed and distributed along the length of the track. However, when the carriers and vanes are retracted and stacked or bunched to one side of the track structure, the rotation rod is unsupported except adjacent the ends thereof. Thus, the rotation rod tends to sag near the center of the rod and the sag may become excessive as the length of the blind structure increases. Similarly, the cord used to traverse the blind vanes will also tend to sag. The sagging of the rotation rod and cord become visible and detract from the appearance of the blind structure.
In addition, such sagging affects mechanical operation of the blinds. For example, a sagging rod has "free play" where the rod is unrestrained, i.e. unsupported by carriers; rotation of the rod to effect rotation of the vanes pivots the rod in the unsupported region thereby whipping the unrestrained rod against adjacent walls of the track structure. This can damage the rods and the track structure, and becomes noisy, thereby detracting from the blind's performance.
In the type of blind structure described in my aforementioned U.S. Pat. No. 4,140,169, a cord arrangement is utilized to effect traverse of the carriers and vanes and only a single rod extends horizontally in the track structure which, as mentioned, is used for rotating the vanes.
In another type of vertical blind structure, two rods extend horizontally in the track structure. One rod is used to rotate the vanes and the other rod is used to traverse the carriers and vanes. This other type of blind structure is described in U.S. Pat. No. 3,190,346 issued to Joseph P. Arena et al. on June 22, 1965, which is incorporated herein by reference. Both rods will tend to sag in this other type of blind structure when the carriers and vanes are retracted and stacked or bunched to one side. Either rod can be whipped against the other or against adjacent walls of the track structure during operation of the blind.